Note 13 - Related Party Transactions - (Details Textual)		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 27, 2020 Merger shares	Jul. 31, 2022 USD ($)	Jun. 30, 2022 USD ($) Property	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) Property	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) Property	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Receivables due from related parties | $			$ 300,000		$ 300,000		$ 100,000
Revenue from related parties | $			$ 300,000	$ 300,000	$ 400,000	$ 800,000
Number of properties to be acquired | Property			2		2		2
Ground lease revenues | $			$ 8,393,000	5,698,000	$ 15,695,000	10,616,000
BBL Property [Member] | Midtown Row [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party | $					$ 122,000,000.0
BBL Property [Member] | Midtown Row [Member] | Subsequent Event [Member]
Related Party Transaction [Line Items]
Related Party Forfeited | $		$ 200,000
Broad Street Entities [Member]
Related Party Transaction [Line Items]
Number of Mergers Remaining | Merger	2
Thomas M. Yockey [Member] | Broad Street Entities [Member] | Common Stock [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	17,985
Thomas M. Yockey [Member] | Broad Street Entities [Member] | Common Stock [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	2,533,650
Thomas M. Yockey [Member] | Broad Street Entities [Member] | OP units [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	136,213
Thomas M. Yockey [Member] | Broad Street Entities [Member] | OP units [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	420,523
Michael Z. Jacoby [Member] | Broad Street Entities [Member] | Common Stock [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	17,985
Michael Z. Jacoby [Member] | Broad Street Entities [Member] | Common Stock [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	2,533,650
Michael Z. Jacoby [Member] | Broad Street Entities [Member] | OP units [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	136,213
Michael Z. Jacoby [Member] | Broad Street Entities [Member] | OP units [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	856,805
Alexander Topchy [Member] | Broad Street Entities [Member] | Common Stock [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	1,934
Alexander Topchy [Member] | Broad Street Entities [Member] | Common Stock [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	137,345
Alexander Topchy [Member] | Broad Street Entities [Member] | OP units [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	14,338
Alexander Topchy [Member] | Broad Street Entities [Member] | OP units [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	48,320
Daniel J.W. Neal [Member] | Broad Street Entities [Member] | Common Stock [Member]
Related Party Transaction [Line Items]
Remaining equity interest to be issued as consideration for the mergers	16,450
Daniel J.W. Neal [Member] | Broad Street Entities [Member] | Common Stock [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	878,170
Samuel M. Spiritos [Member] | Broad Street Entities [Member] | Common Stock [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Related Party Transaction [Line Items]
OP units	13,827
Maximum [Member]
Related Party Transaction [Line Items]
Percentage of management fee					4.00%
Maximum [Member] | Cromwell Field Shopping Center [Member]
Related Party Transaction [Line Items]
Ground lease revenues | $			100,000		$ 100,000
Minimum [Member]
Related Party Transaction [Line Items]
Percentage of management fee					3.00%
BSR [Member] | Thomas M. Yockey [Member]
Related Party Transaction [Line Items]
Consideration to be paid in exchange for repurchasing ownership interest | $									$ 1,500,000
Consideration paid in exchange for repurchasing ownership interest | $								$ 1,000,000.0
Consideration payable in exchange for repurchasing ownership interest | $				500,000		500,000
Timbergate Ventures, LLC [Member] | Thomas M. Yockey [Member]
Related Party Transaction [Line Items]
Related party consulting agreement term							2 years
Related party consulting fees | $				50,000	$ 200,000	100
Related Party Consulting Agreement Expiration Term							Dec. 26, 2021
Shulman Rogers LLP [Member] | Maximum [Member] | Samuel M. Spiritos [Member]
Related Party Transaction [Line Items]
Related party legal fees | $			100,000	$ 200,000	200,000	$ 200,000
Other Assets, Net [Member] | Maximum [Member]
Related Party Transaction [Line Items]
Receivables due from related parties | $			400,000		400,000		$ 200,000
Payables Due to Related Parties [Member] | Due to Properties Managed by Company [Member] | Borrowed by Company for Working Capital [Member]
Related Party Transaction [Line Items]
Payables due to related parties | $			$ 1,200,000		$ 1,200,000		$ 600,000